Anina Yatay Salas is a pensive redhead who really does not like her name. Each part is a palindrome, which means it reads the same both forwards and backwards. Her schoolmates are always teasing her about this, especially Anina’s arch-enemy Yisel. When these two get into a playground fight one day they are sent to the school head who disciplines them with a nerve-racking punishment: they are both given a sealed black envelope which they are not allowed to open for an entire week. Haunted by nightmares, the days drag by endlessly for Anina. She and her inquisitive best friend try to devise all sorts of ways to discover what is inside the envelope. Gradually, Anina begins to realise that not only does Yisel share her fate: she also has much bigger problems to contend with than Anina. Tentatively, the two rivals begin to get to know each other. Narrated by the voice of the young protagonist, the film is able to follow Anina's thought processes and provide an insight into her emotional world. Anina’s day-dreams are not always about her troubles and woes – they also reflect her awakening feelings of love.